1. Field of the Invention
The present invention relates to a crane carrying vehicle for transporting track ties, which comprises an elongated machine frame extending in a longitudinal direction and supported on undercarriages for movement on rails in this direction, the machine frame comprising a tie transporting section for temporarily storing track ties, and a power-adjustable pivotal crane outrigger with a gripping device for gripping track ties.
2. Description of the Prior Art
Such crane carrying vehicles are known from U.S. Pat. Nos. 4,794,861, 4,829,907, 4,884,509, and 4,911,599. These patents described mobile installations for loading, transporting and unloading as well as exchanging railroad track ties, which are comprised of a plurality of work cars as well as freight cars for transporting worn and new ties, the cars being coupled together in a work train. A track is mounted on top of the side walls of gondola-type freight cars, and a gantry crane as well as a crane carrying vehicle run on the track for movement in the longitudinal direction of the installation. The gantry crane is used for removing the worn ties and discharging them into empty freight cars as well as for bringing new ties to the work cars. The crane carrying vehicle has a power-adjustable crane outrigger with a gripping device, which is used to grip a bundle of new ties in the storage space of a freight car, to hoist it and to place it on a longitudinally extending moving conveyor band for temporary storage. This conveyor band is mounted on a frame connected to the machine frame of the crane carrying vehicle and movable therewith so that it forms a tie transporting section from which the gantry crane periodically removes a layer of temporarily stored track ties and moves them to the working site.
A similar crane carrying vehicle on a tie exchange machine is disclosed in U.S. Pat. No. 5,193,461. A vertically adjustable crane outrigger conveys worn and new ties from and to a tie depositing device on the machine, and the machine frame of the vehicle comprises a section for temporarily storing a small number of ties during their transport by the crane carrying vehicle between the machine and the freight cars.
Finally, U.S. Pat. No. 4,955,301 describes a mobile tie exchange machine with a device for pulling worn ties, a device for inserting new ties and a rotatable crane mounted on the machine frame between these devices. The crane enables the worn ties to be temporarily stored on a section of the machine frame during the tie exchange operation.